The invention relates to a high-pressure discharge lamp provided with a discharge vessel, which vessel is enclosed with intervening space by an outer bulb having a lamp cap, as well as with an ignition circuit comprising a voltage-dependent capacitor.
A lamp of the type described in the opening paragraph is known from German Patent DE-C-3330266. In the known lamp, which is suitable for operation in series with a stabilizing ballast from an AC voltage supply source, the capacitor is positioned in the outer bulb and provided with a glass envelope to protect it against reduction and evaporation of parts of the capacitor. Practice has shown, however, that this entails major disadvantages. On the one hand, manufacture of a capacitor provided with such an envelope is very difficult, which makes the capacitor very expensive. On the other hand, the known lamp turns out to have a high degree of early failures owing to capacitor breakdown.
Positioning of the capacitor in the outer bulb, however, is attractive on account of a relatively simple lamp manufacturing method, caused by, among other factors, the availability of comparatively much space, in contrast to, for example, in the lamp cap. The invention has for its object to provide a means by which the disadvantages described are obviated while a comparatively simple lamp manufacturing method is maintained.